World storm surge records
There's still not much to talk about the tropical Atlantic today. The Intertropical Convergence Zone (ITCZ), the band of intense thunderstorms that spans the tropical Atlantic between Africa and the Lesser Antilles Islands, has grown more active in the past few days, though. The two tropical waves in the ITCZ closest to the coast of Africa bear some scrutiny this week as they cross the Atlantic. However, none of the models are currently forecasting development of these waves, and there is plenty of wind shear and dry air that will interfere with potential development.
World storm surge records
In preparation for the release of a major new storm surge section of the web site, I've been researching storm surge records. The Bathurst Bay Cyclone, also known as Tropical Cyclone Mahina, which struck Bathurst Bay, Australia on March 5, 1899, is generally credited with the world record for storm surge. The cyclone's storm surge is variously listed at 13 - 14.6 meters (43 - 48 feet). The Category 5 cyclone was a monster--with sustained winds in excess of 175 mph and a central pressure between 880 and 914 mb. Mahina killed at least 307 people, mostly on pearling ships, and was the deadliest cyclone in Australian history. The eyewitness account of Mahina's record storm surge was provided by Constable J. M. Kenny, who journeyed to Barrow Point on Bathurst Bay to investigate a crime on the day of the storm. While camped on a ridge 40 feet above sea level and 1/2 mile inland, Kenny's camp was inundated by a storm wave, reaching waist-deep. On nearby Flinders Island, fish and dolphins were found on top of 15 meter (49 foot) cliffs. However, an analysis by Nott and Hayne (2000) found no evidence of storm-deposited debris higher than 3 - 5 meters above mean sea level in the region. They also cited two computer storm surge simulations of the cyclone that were unable to generate a surge higher than three meters. Indeed, Bathurst Bay is not ideally situated to receive high storm surges. The Great Barrier Reef lies just 20 - 40 km offshore, and the ocean bottom near the bay is not shallow, but steeply sloped. Both of these factors should conspire to keep storm surges well below the record 13 - 14.6 meters reported. The authors concluded that the actual surge from the Bathurst Bay Cyclone may have been 3 - 5 meters. The observed inundation at 13 meters elevation, plus the observation of dolphins deposited at 15 meters above sea level, could have been caused by high waves on top of the surge, they argue. Waves on top of the surge (called "wave run-up") can reach five times the wave height at the shore for steeply fronted coasts like at Bathurst Bay. Since waves in the Bathurst Bay Cyclone could easily have been 3 meters, 15 meters of wave run-up on top of the surge is quite feasible. Since wave run-up doesn't count as surge, the status of the 1899 Bathurst Bay Hurricane as the world-record holder for storm surge is questionable. However, the event is certainly the record holder for the high water mark set by a tropical cyclone's storm surge, an important category in its own right.
Figure 1. Satellite image of Bathurst Bay, Queensland Province, Australia. The record 43 - 48 foot storm surge wave occurred on Barrow Point, marked by an "x" on the map above. Image credit: NASA.
Figure 2. Track of the 1899 Bathurst Bay cyclone. Bathurst Bay is located at the point where the 914 mb pressure is listed. Image credit: Whittingham, 1958.
Australian storm surge records
The largest storm surges in Australia occur in Gulf of Carpentaria, due to the large expanse of shallow water there (the Gulf of Carpentaria is the large bay to the left of the zoomed-in map of Bathurst Bay shown above). According to an email I received from Australian hurricane scientist Jeffrey Callaghan, "From all reports the storm surge from the disastrous 5 March 1887 cyclone flooded almost all of Burketown (some 30km inland from the Gulf). A copy of a 1918 report to the Queensland Parliament from the Department of Harbours and Rivers Engineer refers to the sea rising to 5.5 metres above the highest spring tide level at the Albert River Heads. This level is about 8 metres (26.2 feet) above Australian Height Datum (AHD). The biggest measured surge in the Gulf of Carpenteria occurred on 30 March 1923, when a surge of 21.4 feet was recorded at a Groote Eylandt Mission".
So what is the world storm surge record if the Bathurst Bay cyclone does not qualify? Well, I haven't researched storms in the Indian Ocean or Pacific Typhoons yet, but it might be difficult to find any storm that beats Hurricane Katrina's 27.8 foot storm surge.
References:
Nott, J, N. Hayne, 2000: How high was the storm surge from Tropical Cyclone Mahina?", Australian Journal of Emergency Management, Autumn 2000.
Anonymous, 1899, The Outridge Report--The Pearling Disaster 1899: A Memorial", The Outridge Company, 1899
Whittingham, 1958, "The Bathurst Bay hurricane and associated storm surge", Australian Meteorological Magazine, No. 27, pp. 40-41. Scanned and put on-line courtesy of John McBride.
I'll have an update on Tuesday, when the latest CSU seasonal hurricane forecast comes out at 11am EDT.
.
Jeff Masters
Reader Comments
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Haiti, I thought because didn't the whole side of the country (if that's what you want to call it) was deforestated. :)
THE ITCZ AXIS IS CENTERED ALONG 14N15W 9N29W 11N42W 9N50W
12N61W. BROAD AREA OF MID LEVEL CYCLONIC ROTATION IS EMBEDDED
WITHIN THE ITCZ NEAR 9N29W WHERE A SURFACE TROUGH WILL BE
ANALYZED AT 04/0000 UTC. SCATTERED TO NUMEROUS STRONG CONVECTION
IS WITHIN A 60 NM RADIUS OF 9N31W. SCATTERED MODERATE TO
ISOLATED STRONG CONVECTION COVERS THE REMAINDER OF THE AREA FROM
6N-11N BETWEEN 27W-33W. CLUSTERS OF ISOLATED MODERATE CONVECTION
DOT THE AREA WITHIN 200 NM EITHER SIDE OF THE ENTIRE ITCZ."
Interesting
Dont jump the gun just yet
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT MON AUG 3 2009
FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...
TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE NEXT 48 HOURS.
$$
FORECASTER SCHAUER CLARK/BRENNAN
Per wikipedia...."Vorticity is a concept used in fluid dynamics. In the simplest sense, vorticity is the tendency for elements of the fluid to "spin."".....
850 mb's is near the surface.
thats exactly what i expected. unless the area is an invest or very close to an invest they wont give it even a <30 percent chance. very conservative this year but the wave isn't as good-looking as a lot are making it out to be
I am really stuned!
Im not
Rotating winds.
456,What do the steering currents look like for this one?
vorticity is basically the amount of spin that is in the atmopshere. Positive vort is counterclockwise flow, while negative vort is clockwise flow in the Northern Hemisphere.
It doesnt deserve one yet, patience
it seems it will go wnw, that high is sprawling. And since we don't know if it will develop, shallow to mid-level steering will likely control this system until development occurs.
Me too.
LOL you sound so full of it really
Who is we anyway?
yep its basically the spin, around a vertical axis. We need it in order to confirm a low and how strong/weak it is.
Is that the "royal" we? Err...maybe ya might wanna let the NHC in on this...
Im Uptown...eating a Grape Snowball,
...Urrrrrrp
'LONG RANGE OUTLOOK: THE CLIMATE FORECAST SYSTEM (CFS) AND THE
EMPIRICAL WAVE PROPAGATION (EWP) MODELS SHOW MJO OVER THE DOMAIN
GRADUALLY BECOMING FAVORABLE...WITH BOTH SHOWING CONDITIONS
IMPROVING FOR TROPICAL STORM FORMATION OVER THE TROPICAL
ATLANTIC/EASTERN CARIBBEAN DURING THE SECOND WEEK IN AUGUST.
THEY...HOWEVER...DIFFER ON HOW LONG CONDITIONS ARE TO REMAIN
FAVORABLE...WITH THE EWP SHOWING FAVORABLE CONDITIONS FOR UP TO
THREE WEEKS...WHILE THE CFS TAPERS OFF AFTER TWO. WE ARE DUE FOR A
LONG STRETCH...SO WE ARE LEANING IN FAVOR OF WHAT THE EWP
SUGGESTS.'
Could be our next invest brewing around 9N 32 W.
'LONG RANGE OUTLOOK: THE CLIMATE FORECAST SYSTEM (CFS) AND THE
EMPIRICAL WAVE PROPAGATION (EWP) MODELS SHOW MJO OVER THE DOMAIN
GRADUALLY BECOMING FAVORABLE...WITH BOTH SHOWING CONDITIONS
IMPROVING FOR TROPICAL STORM FORMATION OVER THE TROPICAL
ATLANTIC/EASTERN CARIBBEAN DURING THE SECOND WEEK IN AUGUST.
THEY...HOWEVER...DIFFER ON HOW LONG CONDITIONS ARE TO REMAIN
FAVORABLE...WITH THE EWP SHOWING FAVORABLE CONDITIONS FOR UP TO
THREE WEEKS...WHILE THE CFS TAPERS OFF AFTER TWO. WE ARE DUE FOR A
LONG STRETCH...SO WE ARE LEANING IN FAVOR OF WHAT THE EWP
SUGGESTS.'
Could be our next invest brewing around 9N 32 W.
1. SHOWERS AND THUNDERSTORMS ASSOCIATED WITH AN AREA OF DISTURBED
WEATHER LOCATED ABOUT 1150 MILES SOUTHWEST OF THE SOUTHERN TIP OF
BAJA CALIFORNIA HAVE CONTINUED TO BECOME BETTER ORGANIZED...AND A
TROPICAL DEPRESSION MAY BE FORMING. IF CURRENT TRENDS CONTINUE...
ADVISORIES MAY BE INITIATED LATER THIS EVENING AS THE SYSTEM MOVES
WESTWARD OR WEST-NORTHWESTWARD AT AROUND 15 MPH. THERE IS A HIGH
CHANCE...GREATER THAN 50 PERCENT...OF THIS SYSTEM BECOMING A
TROPICAL CYCLONE DURING THE NEXT 48 HOURS.
No, they aren't. If I had a job as a forecaster there, I wouldn't have mentioned it either. I explained yesterday on AIM that 1988's Isaac developed from a vigorous perturbation in the ITCZ, developing the moment it detached, true, but that appears to have been an exception. Many disturbances within the ITCZ derive most, if not all, of their energy from the ITCZ. But if they are located within a stable environment like the one currently in the EATL, then they begin to struggle to organize until reaching a more moist airmass.
NHC probably did not mention it, because its low-level vorticity is minimal, and it is still confined to the ITCZ, being sustained only by it.
No offense, but no one can predict long-range with even any remote degree of accuracy.
And besides, you aren't a met...
And I daresay this is mere wishcasting on your part after Gustav and Ike last year, and you just happened to have been right so far on an uneducated guess motivated by hope.
Thanks,these areas of low pressure are common this time of year for us,they pass and dump excessive amounts of rainfall.
Deforestation is most rampant in Haiti.
I see that....5,000 feet above sea level.
Viewing: 901 - 951
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